The advisory is in effect until 9 p.m. Thursday. Residents from the coast to the Research Triangle area could experience unhealthy air quality, and especially sensitive groups are advised to avoid or reduce prolonged or heavy exertion outdoors.

Firefighters and emergency response officials are urging people who see and smell smoke not to call 911 unless they see a fire, a smoke column or wish to report someone burning irresponsibly.

The fire in the Alligator River National Wildlife Refuge is creating heavy smoke that could contain high levels of particle pollution.

Forecasters have predicted Code Red, or unhealthy air quality, in southern Dare and eastern Hyde counties.

Fire crews have created a 571 acre burnout line and are air lifting water in to try to put out the blaze.

Officials say arson is being investigated as the cause of the fire. They also say no homes are in jeopardy.